const pathSum = (root, sum) => {
    if(!root) return 0;

    let leafCountSet = new Set();
    let pathsSet = new Set();

    const checkSum = (valSeqs, pathSeqs, sum) => {
        const vals = valSeqs.slice(0, valSeqs.length - 1).split(',');
        const paths = pathSeqs.slice(0, pathSeqs.length - 1).split(',');
        const sums = [];
        const pathsStrs = [];

        vals.forEach( (val, key) => {
            for (let i = 0; i <= key; i++) {
                if(typeof(sums[i]) === 'undefined') {
                    sums[i] = parseInt(val, 10);
                } else {
                    sums[i] += parseInt(val, 10);
                }


                if(sums[i] === sum) {
                    // console.log('df');
                    const pathStr = paths.slice(i, key).join('-');
                    const sumsStr = sums.join('-');
                    pathsStrs.push(pathStr + '-' + sumsStr);
                }
            }
        })

        // console.log('vals', valSeqs);
        // console.log('pathSeqs', pathSeqs);

        return pathsStrs;
    }

    const recursivePath = (root, sum, valSeqs = '', pathSeqs='', key='') => {

        if(root == null) {
            const sumId = checkSum(valSeqs, pathSeqs, sum);
            if(typeof(sumId) !== 'undefined') {
                sumId.forEach( path => leafCountSet.add(path))
            }
            // console.log('valSeqs', valSeqs);
            pathsSet.add(valSeqs);
            return;
        }

        if(key) pathSeqs += key + ',';

        if(typeof(root.val) !== 'undefined') {
             valSeqs += root.val + ',';
        }

        recursivePath(root.right, sum, valSeqs, pathSeqs, 'right');
        recursivePath(root.left, sum, valSeqs, pathSeqs, 'left');
    }

    recursivePath(root, sum);
    console.log(leafCountSet);
    // console.log('-----------');
    console.log('valSeqs', pathsSet);
    return leafCountSet.size;
};